Device for the pressure processing of a continuous particularly textile web

ABSTRACT

An apparatus for uniformly pressure treating a running web, such as an apparatus for squeezing a textile web, with two outer rollers rotating in the same direction, and a central roller arranged between and slightly ahead of the outer rollers to define with one of them a working gap, in which the central roller, for purposes of closing the gap is movable towards the gap, one of the outer rollers being driven by a differential transmission which includes a main drive member and an auxiliary drive member for this outer roller, while the outer roller drives the auxiliary drive member.

United States Patent Friedrich Kunze Zittau, Germany Aug. 12, 1968 Mar. 2, 1971 Veb Textilmaschinenbau Zittau Zittau, Germany inventor Appi. No. Filed Patented Assignee DEVICE FOR THE PRESSURE PROCESSING OF A CONTINUOUS PARTICULARLY TEXTILE WEB 5 Claims, 11 Drawing Figs.

[56] References Cited UNITED STATES PATENTS 1,938,444 12/1933 Vedder 100/176X 3,331,734 7/1967 Rojecki 100/160X Primary ExaminerEdward L. Roberts Attorney-Nolte and Nolte ABSTRACT: An apparatus for uniformly pressure treating a running web, such as an apparatus for squeezing a textile web, with two outer rollers rotating in the same direction, and a central roller arranged between and slightly ahead of the outer rollers to define with one of them a working gap, in which the central roller, for purposes of closing the gap is movable towards the gap, one of the outer rollers being driven by a differential transmission which includes a main drive member and an auxiliary drive member for this outer roller, while the outer roller drives the auxiliary drive member.

Patented March 2, 1971 3 Sheets-Sheet 1 E m2 N WU mK w k 0 m F *VMHMMQ ATTORNEYS Patnted March 2, 1971 3,566,781

3 Sheets-Sheet I INVENTOR FP EDfi/Ch KVNZE' by MA ml now ATTORNEYS Patented March 2,1971 3,566,781

3 Sheets-Sheet .5

by mm M1 M1 ATTORNEY:

DEVICE FOR THE PRESSURE PROCESSING OF A CONTINUOUS PARTICULARLY TEXTILE WEB BACKGROUND OF THE INVENTION The present invention relates to a device for pressure treatment of a running web, especially a textile web, with two outer rollers rotating in the same direction and an intermediate roller. Between the intermediate roller and one of the outer rollers the working gap is formed. The space between the two outer rollers is smaller than the diameter of the intermediate roller, the intermediate roller being located in front of the space between the two outer rollers, when looking in the direction of rotation of the rollers.

Numerous devices for the pressure treatment of webs with two, three or more rollers are known, in which, for purposes of producing a pressure which is uniform over the entire length of the rollers, an undesired bending of the rollers in the direction away from the effective side of the rollers is to be prevented or compensated. In principle, these goals are supposed to be achieved by providing special inner and/or outer supports or by a particular form of the rollers. With all such arrangements, whether with two, three or more rollers, the load on the working gap is supplied in the usual manner by a loading device associated with at least one of the outer rollers. Aside from the fact that such devices are very expensive and liable to disturbances and breakdowns, this goal is achieved in only a few cases.

Recently a new solution has been suggested by a device in which the pressure in the working gap is provided solely by the rotation of the rollers which are interconnected by frictional forces. In this arrangement, the two inner rollers are pulled in between two driven outer rollers, in the direction of rotation. Since the sum of the diameters of the inner rollers is larger than the gap between the outer rollers, the outer rollers exert a wedgelike action upon the inner rollers whereby a pressure is exerted by the inner rollers onto the web passed through therebetween. This arrangement is, however, disadvantageous for the reason that two intermediate rollers are required and that only minor pressures are obtainable, since the intermediate rollers press themselves into the gap between the outer rollers only with the counterforce created therebetween, which force is solely exerted by the web itself. Due to the fact that the two outer rollers are driven at their axes of rotation, in the roller system, a forced run" or positive drive is caused which leads to the destruction of elastic layers on the rollers.

Another disadvantage with all heretofore known squeezing apparatus which serve for squeezing out the medium contained in a web, consists in that, in view of the deformation of the elastic circumferential portion of the roller, on the inlet side of the working gap a protrusion or bead is formed whereas the elastic portion at the outlet side thereof is reduced. Consequently, a very undesirable widening of the working gap on the inlet side is created so that the removal of the squeezed-out medium is impeded on the inlet side and a portion of the medium escapes to the outlet side to thereby decrease the efficiency of the squeezing operation.

It is, therefore, an object of the present invention to provide an apparatus for the pressure treatment of webs, especially textile webs, which will overcome the above-mentioned disadvantages of heretofore known such devices.

It is another object of the present invention to provide a device of the type just referred to,. by means of which a uniform and high pressure can be obtained in the working gap of the device.

Another object of the invention consists in the provision of an apparatus of the general type referred to above, in which the working gap has a form or shape which increases the efficiency of the squeezing operation and in which a favorable ratio between the power necessary for the drive and the output of the roller system is obtained.

It is a still more specific object of the present invention to provide an apparatus of the above type in which the load on the working gap is solely brought about by the rotation of the rollers of a three-roller system.

BRIEF SUMMARY OF THE INVENTION In accordance with the present invention, the intermediate roller of a three-roller system is, for purposes of closing the orking gap, moved toward the space between the two outer rollers by the arrangement in which one of the two outer rollers is driven at its axis of rotation by a differential transmission, which, for this outer roller has, aside from a main drive member, an auxiliary drive member, said auxiliary drive member being driven by the other outer roller.

The relief of the intermediate roller is effected by means of an additional transmission provided with a clutch by means of which the two outer rollers are rigidly drivingly interconnected. r I

The intermediate roller has associated therewith a correction means by means of which the force exerted by the outer rollers onto the intermediate roller can be corrected or adjusted for purposes of closing the working gap.

Between one outer roller and the auxiliary drive member driven thereby, a control transmission may be arranged.

The intermediate roller is, in a manner known per se, provided with an elastic surface layer. While this elastic layer is advanced in the gap between the outer roller and the intermediate roller driven thereby with respect to the core of the roller, a braking effect is exerted upon the same in the gap between the intermediate roller and the 'outer roller driven thereby.

BRIEF DESCRIPTION OF THE DRAWING V tached drawing, in which:

FIG. 1 is a side view of a squeezing apparatus designed in conformity with the present invention, including the drive for the apparatus;

FIGS. 2 to 4 are respectively cross sections taken along the lines A-A, 8-8 and C-C of FIG. 1;

FIG. 5 illustrates the support for the intermediate roller of the apparatus according to FIG. 1;

FIGS. 6 to 9 illustrate the behavior of the elastic circumferential portion of a roller under several load conditions;

FIGS. 10 and 11 diagrammatically illustrate examples of drive for the apparatus according to FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to the drawings in detail, and FIGS. 1 and 2 thereof in particular, these FIGS. illustrate a squeezing apparatus, in principle. This squeezing apparatus, generally designated with the reference numeral S, comprises a system of several rollers and a drive therefor. The system of rollers comprises two outer rollers l and 2 having a smooth surface and an intermediate elastic-surfaced roller 3. Whereas the rollers 1 and 2 are stationarily supported, roller 3 is adjustable in the direction of the space formed between rollers l and 2. The space between rollers l and 2 is smaller than the diameter of roller 3. A web of material 4, such as textile material, is guided through the working gap formed between rollers 1 and 3 in the direction of rotation of the rollers l and 3. Roller 3, when looking in the direction of movement of the web is arranged in front of the space between rollers l and 2.

The axles or trunnions of roller 3 are displaceable in guiding means 5. The drive for the apparatus comprises a motor M having connected thereto a transmission 6. Transmission 6 is drivingly connected to the bevel gear 7 of a differential transmission D, which also includes two bevel gears 8 and 9 rotatably supported on a pin 10. Pin 10 is connected for movement with the trunnion 11 of roller 1. Bevel gears 8 and 9 are also in driving connection with a bevel gear 12 which is rotatably mounted on trunnion ll. Bevel gear 12 is connected to a gear ring 13 which meshes with a gear 15 through the inthereto, is rotated if a counter force acts upon bevel gears 8 i and 9 through the intervention of bevel gear 12. This counter force is obtained due to the drive connection of bevel gear 12 with roller 2 via gear ring 13, intermediate gear 14 and gear 15. Pin 10 thus operating as output member of the drive causes the revolution of roller 1.

Since roller 3 which is movable in the direction of the space provided between rollers 1 and 2 is held in cooperating relation with the rollers l and 2 so that the rollers 1, 3 and 2 act as a roller drive, the rotation of roller 1 is transmitted via roller 3 to roller 2 which, therefore, rotates in the same direction as roller 1. The momentum MA (see FIG. 2) transmitted to roller 1 has to overcome the counter momentum MG which is effective at roller 2 through the intervention of a connection between the roller 2 and the bevel gear 12 as described above. In this way, a pretension or preload is formed in the roller system. The countertorque MG is produced by the motor M exerting through the transmission 6 and differential gear 7, 8, 9, 10 an oppositely directed torque on the bevel gear 12. The rotation of roller 2, through the intervention of gear 15, intermediate gear 14 and gear ring 13 causes a rotation of bevel gear 12 in the direction of rotation of bevel gear 7 whereby bevel gear 12 becomes effective as an auxiliary drive of pin 10 and, thereby, of roller 1. In this way, the power transmitted from roller 1 via roller 3 to roller 2 is returned to the drive of roller 1. The forces P1 and P2 occurring during the transmission of a momentum from roller 1 to roller 2 at the points of contact between rollers 1 and 3 and 3 and 2 exert a pulling force upon roller 3 in the direction indicated by the reference character X, which brings about a pulling force on roller 3 into the space between rollers I and 2 and, therefore, as a result of a wedging action, brings about a pressing force at the lines of contact between roller 3 and rollers 1 and 2 (FIG. 2). This pressing force brings about a bending of rollers 1 and 2 towards that side which faces away from the location where the squeezing action takes place.

Since roller 3 runs in journal bearings 34, 35, which can be adjusted and locked in guides 5.1 the retracting force can not pull roller 3 between the two rollers l and 2. This retracting force acting in the direction x causes, however, also a horizontal bending of roller 3 corresponding to the sum of the transmission forces P1 and P2 acting as shearing forces. As mentioned above, the journal bearings 34, 35 can be adjusted and locked in guides 5. The horizontal bending of roller 3 can be so influenced that the bending caused by the pressure of the rollers 1 and 2 on roller 3, upward (roller 1) and downward (roller 2) is compensated by the fact that a uniform pressure is achieved over the entire length of the working gap, the interval between the two rollers l and 2. For all cross-sectional planes of the roller drive system different angular positions of the three rollers with respect to each other are obtained. Thus, FIG. 3 shows possible relative positions in the center of the rollers, whereas FIG. 4 shows such positions for the marginal or end portions of the rollers. (For purposes of clarification, the differences in the angular positions are exaggerated.)

As shown in FIG. 5, rollers 3 can be provided with bearings 34, 35 which are acted upon by correcting" means 36 by means of which the pulling force exerted upon roller 3 can be corrected. The guides 5, in which the journal bearings 34, 35 can be adjusted and locked, can be in the form of rails, as in the embodiment shown. The correcting means 36 in this embodiment conventionally comprises an adjusting motor or its equivalent. The movement of roller 3 is limited by adjustable abutments 30, 31, 32, 33. The magnitude of the counter force acting in roller 2 is determined by the transmission ratio between the bevel gear 12 and the gear 15. The transmission ratio is selected corresponding to the magnitude of the countertorque MG. The control of the magnitude of the counter force may be effected, as is well known in the art, by change gears, stepping gears, variable speed transmissions or the like. In FIG. 1, gears 14 and 15 are designed as change gears.

In view of the fact that by retransfer of the rotational energy transmitted to roller 2 onto the drive for roller 1, as driving power for the squeezing apparatus only the energy required for the rotation of the pretensioned system including the energy required for the kneading work has to be impressed upon the system.

The power ratio between the motor drive and the inner power of the roller system is determined the ratio of the rotational speed and of the momentum of the two bevel gears 7 and 12 of the differential transmission D as well as by the transmission ratio between roller 2 and bevel gear 12. Fundamentally, due to the above arrangement the internal load of roller gears, by which the required squeezing force is produced, is larger than the required drive power.

Since the load in the working gap exists only during the rotation of the roller system, a relief of the load is obtained solely by elimination of the driving momentum.

If, during the operation of the apparatus, for instance, for the passage of a seam or another impediment interfering with the proper operation of or causing a danger to the system, the pressing force is to be relieved, this is effected by the direct driving connection of rollers l and 2 by means of an additional transmission. As shown in FIG. 1, a gear 16 is fixedly connected with the shaft 11. This shaft 11 drives a gear 19 rotatably journaled on a shaft 18 through the intervention of an intermediate gear 17 movably journaled in the frame of the apparatus.

For purposes of relieving the squeezing apparatus, gear 19 is drivingly connected with shaft 18 and thereby with roller 2 through the intervention of a clutch 20, for instance, an electromagnetic clutch. In this way, roller 2 is directly driven by roller 1 through the intervention of gear 16, intermediate gear 17 and gear 19 and with the same speed of rotation or with a higher speed. The drive of roller 2 is thus effected through the gear wheels l6, l7, l9 and no longer by roller 3, which is thus relieved of the driving forces and exerts no pressure any more. In view of the fact that the counter momentum at roller 2 is eliminated, an immediate relief is effected. In normal operation of the squeezing apparatus, clutch 20 is open.

The behavior of the elastic circumferential portion of a roller can best be understood from a description of a pair of rollers shown in FIGS. 6 to 9. Roller 21 is a hard roller, for instance, a steel roller, whereas roller 22 is a roller with an elastic circumferential portion.

The displacement of the elastic material is, under a heavy load, in the rest position (FIG. 6) the same towards both sides. If one of the rollers is driven, in FIG. 7 roller 22 by a force PA, the elastic circumferential portion is deformed to form a bead at the inlet side of web 4 into the roller system. The deformed portion or bead on the inlet side is still further increased (FIGS. 7 and 8) when roller 22 is driven in the direction of the force PA and when a braking force is effective on roller 21 in the direction indicated by PG.

A displacement of the deformed portion or bead towards the outlet side of the roller system occurs, as shown in FIG. 9, when the hard roller 21 is driven in the direction of the force PA and when a braking force is effective at elastic roller 22 in the direction PG during rotation. This is clearly visible when roller 22 is brought to a complete stand-still.

The deformation of the elastic circumferential portion shown in FIG. 9 also occurs with the system as shown in FIGS. 1 to 4; l0 and 11, between rollers 1 and 3. This deformation is brought about by the counter momentum effective at roller 2.

The deformation of the elastic circumferential portion described and shown in FIG. 8 occurs between rollers 3 and 2. This phenomenon occurring at a location where pressure is exerted is made use of, when operating the three-roller system as a squeezing apparatus, by guiding'web 4 between rollers l and 3 in the direction of rotation of these rollers or, when using the system for pressing fluid into web 4, by guiding web 4 between rollers 3 and 2 in the direction of rotation thereof.

As shown in FIGS. and 11, it isalso possible to reverse the function of the members of the differential transmission, while no change is being effected in the described principle of operation. More specifically, in FIG. 10 bevel gear 23 is employed as the main drive member and pin 24 serves as auxiliary drive member. The power of the motor is introduced into bevel gear 23, and bevel gear 25 is drivingly connected with roller 1. Pin 24 is drivingly connected with roller 2 via a gear ring 26, an intermediate gear 27 and a gear 28.

in FIG. 11, pin 24' serves as main drive member while the power of the motor is impressed upon pin24' by means of a gear ring 26. Bevel gear 23' sewing as auxiliary drive is drivingly connected to roller 2 through the intervention of gears 29 and 28. Bevel gear 25 is drivingly connected with roller 1.

Instead of the differential gear described above, also other drives may be employed, as mechanical equivalents of the differential transmission disclosed above, and such drives are included in the expression differential transmission unless expressly excluded.

For instance, in conformity with the above principles, planetary gear drives may be employed. It is, for instance, possible to employ a planetary gear with a sun gear, with a pin with several planetary wheels and 'withan outer gear having inner teeth. Depending on the reduction available with such a transmission, the ratio of driving force and counter momentum can be adjusted as required.

it is to be understood the ratios of the diameters shown in the drawings for the rollers as well as the position of the axes of the rollers with respect to each other are not to be considered as fixed, but that they can be changed and modified in conformity with various requirements.

The invention achieves the result that the very disadvantageous features of heretofore known squeezing apparatuses have been eliminated, such as bending of the rollers and deformation of the surface of the elastic roller and that the efficiency of the squeezing apparatus is at an optimum.

While preferred embodiments of the invention have been described above, it is to be understood that the invention is not restricted thereto, but is determined solely by the attached claims.

I claim: 1. An apparatus for pressure treating a'running web, especially textile web, comprising two outer rollers arranged substantially parallel to each other and rotatable in the same direction, a central roller located between said two outer rollers and defining together with one of said outer rollers a working gap for receiving a web therein, the space formed between said two outer rollers being smaller than the diameter of said central roller, said central roller being arranged in front of said space when looking in the direction of movement of a web through said apparatus and being movable toward and away from said space, and differential transmission means drivingly connected to one of said outer rollers, said transmission means including a main drive member and an auxiliary drive member both operatively connected to said one outer roller, said auxiliary drive member being drivingly connected to the other outer roller.

2. An apparatus according to claim 1, which comprises an additional transmission means and clutch means for rigidly drivingly interconnecting said two outer rollers.

3. An apparatus according to claim 1,. which comprises means operatively connected to said central rollerfor adjusting the force exerted by said outer rollers 'o'n'sai' entral roller for closing said working gap. 4

4. An apparatus according to claim 1, whic trol transmission means interconnecting one of 'said outer'rollers and said auxiliary drive member 5. An apparatus according to claim 1, wherein said central roller is provided with circumferential layer of elastic material.

includes con-1. 

1. An apparatus for pressure treating a running web, especially textile web, comprising two outer rollers arranged substantially parallel to each other and rotatable in the same direction, a central roller located between said two outer rollers and defining together with one of said outer rollers a working gap for receiving a web therein, the space formed between said two outer rollers being smaller than the diameter of said central roller, said central roller being arranged in front of said space when looking in the direction of movement of a web through said apparatus and being movable toward and away from said space, and differential transmission means drivingly connected to one of said outer rollers, said transmission means including a main drive member and an auxiliary drive member both operatively connected to said one outer roller, said auxiliary drive member being drivingly connected to the other outer roller.
 2. An apparatus according to claim 1, which comprises an additional transmission means and clutch means for rigidly drivingly interconnecting said two outer rollers.
 3. An apparatus according to claim 1, which comprises means operatively connected to said central roller for adjusting the force exerted by said outer rollers on said central roller for closing said working gap.
 4. An apparatus according to claim 1, which includes control transmission means interconnecting one of said outer rollers and said auxiliary drive member.
 5. An apparatus according to claim 1, wherein said central roller is provided with circumferential layer of elastic material. 